SpaceX said that decision was “arbitrary and capricious and contrary to law”, and favoured established launch providers.

The LSA agreements help companies offset the costs of meeting the US government's particular launch requirements for the upcoming launch procurement competition for government launches in the period 2020-24.

Without LSA funding, SpaceX will have to carry substantial but unspecified launch costs on its own, including constructing a payload integration facility at the Eastern Range launch complex.

A spokesman for SpaceX told US space sector website SpaceNews that it was challenging the USAF launch service agreement decision to ensure a level playing field.

The legal action sets out detailed reasons explaining why SpaceX believes the court should declare that the LSA awards decision violates the requirement for competitive procedures.

It seeks the court to halt further government LSA investments and to require a re-evaluation of SpaceX’s proposal.

SpaceX is especially critical of what it said is institutional bias in favour of long established and dominant space launch provider ULA, a joint venture of Boeing and Lockheed Martin.

Litigation involving SpaceX and ULA is nothing new. As far back as 2005, SpaceX unsuccessfully sought to challenge the ULA monopoly on launch services using US anti-trust laws. In 2013, SpaceX sued the USAF over its decision to award ULA a bulk purchase of launches rather than conduct a competitive bids process.

In the latest litigation, SpaceX claims that the USAF chose the portfolio that best served the interests of ULA and that its Falcon 9 and Falcon Heavy have launched more than 70 national security, civil and commercial missions.

SpaceX describes the three LSA winner vehicles as “paper rockets” that would not be ready in time to start actual payload launches in 2022.

SpaceX said it doesn’t want to delay or halt the National Security Space Launch Phase 2 Launch Service Procurement, just to allow an independent third party to review a decision it considers flawed.

It said it will suffer substantial competitive harm through being deprived the opportunity to compete fairly.

The winners Blue Origin, Northrop Grumman and ULA have all filed motions to intervene in the SpaceX lawsuit.